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- Path: ousrvr3.oulu.fi!kinnunen
- From: kinnunen@stekt.oulu.fi (Teijo Kinnunen)
- Newsgroups: comp.sys.amiga.misc
- Subject: Re: OS features
- Date: 7 Jan 1996 23:57:51 GMT
- Organization: University of Oulu, Department of Electrical Engineering, Finland
- Message-ID: <4cpmlv$obe@ousrvr3.oulu.fi>
- References: <92747544038@PAPA.NORTH.DE> <4b3h9s$1st@alterdial.UU.NET> <2152.6561T63T2136@cycor.ca> <4b7i18$si1@vixen.cso.uiuc.edu> <oj6raxxrr0o.fsf@hpsrk.fc.hp.com> <13213431@sourcery.han.de>
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- Olaf Barthel (olsen@sourcery.han.de) wrote:
-
- > The idea to have better protection against rogue tasks sounds
- > good enough already. I agree that it would be terribly nice to
- > have memory protection, but as it stands the chances to implement it
- > without losing overall software compatibility are so low they could
- > walk through below a closed door.
-
- I will absolutely want to use an OS with memory protection in the future,
- so I guess it won't be AmigaOS then :-/.. The situation is a bit ironical.
- Years ago Amiga users used to laugh at excuses why multitasking isn't
- necessary, today I see some Amiga users telling how we don't need memory
- protection. It's analoguous, yesterday some major OSs could multitask,
- today everyone can. Today some major OSs have memory protection,
- tomorrow everyone has. I wish AmigaOS was among them.
-
- > This really calls for a different OS. One idea that has been brought
- > forward was to come up with a scheme that allows for different processes
- > to run in different memory spaces, very much like running multiple
- > AmigaOS sessions on the same machine. That way you can gun an environment
- > that has crashed and see the other environments survive. But there is a
- > problem to solve: how to implement shared memory accesses and interprocess
- > communication without running into the same trouble the original Amiga
- > shared memory space causes?
-
- How about something like this (just an idea):
- All "old" applications run in a single memory space, with no protection
- between them, if one of them crashes, this virtual machine may crash bringing
- possibly down all "old" programs with it. They can communicate with each
- other using shared memory & messages, as they do today.
- "New" programs (aware of memory protection) would each run in their own
- protected memory spaces (with resource tracking, hopefully). They could
- communicate with other processes only through new, safe OS calls (not by
- sharing memory, as today). These new programs could crash without harming
- any other processes, and they could be completely killed releasing all
- the resources they used.
- "Old" programs should be convertable to "new" with relatively few changes,
- mostly concerning interprocess messaging, and recompilation.
-
- There's no easy way to add MP to AmigaOS, but as far as I can think of,
- the above method would allow some level of compatibility with old programs.
-
- - Teijo
-
- --
- o------------------------------------------------------------------o
- / Teijo Kinnunen - Valkkyla 7 as 413 - 90100 OULU - FINLAND /
- / Student at University of Oulu, Dept. of Electrical Engineering /
- / Teijo.Kinnunen@oulu.fi -- http://stekt.oulu.fi/~kinnunen/ /
- o------------------------------------------------------------------o
-